1. Field of the Invention
The present invention relates to a printer, and more particularly, it relates to a printer comprising a print head portion capable of emitting a laser beam.
2. Description of the Background Art
A printer comprising a print head portion capable of emitting a laser beam is known in general. Such printers are disclosed in Japanese Patent Laying-Open Nos. 08-290594 (1996), 08-174871 (1996) and 07-171992 (1995) and National Patent Publication Gazette No. 2005-503275, for example.
Each of the printers disclosed in the aforementioned Japanese Patent Laying-Open Nos. 08-290594 and 08-174871 is so formed as to apply a laser beam to an ink sheet superposed on a paper and wound on a rotating drum along with the paper.
In each of the printers disclosed in the aforementioned Japanese Patent Laying-Open Nos. 08-290594 and 08-174871, however, the ink sheet remains wound on the rotating drum still in close contact with the paper in a nonprinting state, whereby the ink of the ink sheet disadvantageously slightly adheres to the overall paper due to the contact between the ink sheet and the paper over a long period.
In order to solve the aforementioned problem, Japanese Patent Laying-Open No. 07-171992 proposes a technique capable of inhibiting the ink of an ink sheet from slightly adhering to the overall paper.
The aforementioned Japanese Patent Laying-Open No. 07-171992 discloses a sublimatic laser printer comprising a bobbin (cartridge) dedicated to an ink sheet so that the ink sheet may not be superposed on a paper over a long period, for bringing the ink sheet into contact with the paper at an extremely small width with a semi-columnar transparent press bar and sublimating the ink with a laser beam thereby preventing the ink from slightly adhering to the overall paper.
A printing system capable of thermally transferring a signature required by a substrate such as a credit card from a thermal foil member brought into pressure contact with the substrate to the substrate with a laser beam is also known in general, as disclosed in the aforementioned National Patent Publication Gazette No. 2005-503275.
However, the sublimatic laser printer disclosed in the aforementioned Japanese Patent Laying-Open No. 07-171992 simultaneously moves the ink sheet and the paper brought into contact with each other by the press bar in the same direction (first direction) for transferring the ink from the ink sheet to the paper. When performing printing by successively transferring inks from ink sheets of three colors of Y (yellow), M (magenta) and C (cyan) to the paper, therefore, the sublimatic laser printer must transport the paper in a second direction opposite to the aforementioned first direction for returning the same to the original printing start position every time the paper is printed with one of the three colors, whereby the number of times for transporting the paper in printing is disadvantageously increased.
The printing system described in the aforementioned National Patent Publication Gazette No. 2005-503275 transfers the signature to the substrate with a pressure and heat, to disadvantageously require a pressurization mechanism for applying a pressure in addition to the laser beam serving as a heat source.